At present, AMOLED screens are used in more and more cell phones. In an existing AMOLED screen, three sub-pixels of red, green and blue are prepared by using a fine metal mask (FMM). However, since requirements for screen resolutions are getting higher and higher, such technology for manufacturing the existing AMOLED screen cannot meet the requirements due to limitations of accuracy of the FMM. A combination of a top-emitting white organic light emitting diode (OLED) and a color filter (CF) is more suitable for manufacture of high-resolution AMOLED display devices.
An OLED has many advantages, such as light weight, thin thickness, high brightness, high response speed, wide viewing angle, no backlight, low manufacturing costs, and bendability. In a white OLED, a variety of fluorescent materials or phosphorescent materials that can emit different colors are combined, so that the white OLED can emit white light. However, the white OLED has a strong microcavity effect, and it is difficult to simultaneously emit white light with three peaks of red, green and blue. Thus, after white light passes through a color filter (CF), three primary colors of red, green and blue obtained have relatively poor purities. In order to overcome a microcavity effect of a top-emitting white OLED (WOLED), conventional practice is to increase thicknesses of anodes of the three sub-pixels of blue, green and red sequentially to adjust requirements of different light colors on cavity lengths. As shown in FIG. 1, such a structure is complicated and is difficult to be manufactured.